Great stability, very fine. It's a SG3525/2 inch. core/4 X IRGPC30U/ half bridge SMPS project. In the start, I built it with IR2110 but I don't understand, the IGBTs stay very hot no load and the IR2110 explode after few minuts. Now, I get out the IR2110 and built a small core driver. Very good enjoy because the IGBTs stay "ice" and no fan is necessary in hard load.